‘If you find the right person,’ the captain said, ‘the fact that they are untried shouldn’t be a problem. Cryptography is like falling in love: just because you’ve fallen in love loads of times before doesn’t mean the relationship is going to work out. Emotional involvement is crucial, as are fate and intelligence.’ He suggested that we visit the Institute of Mathematics at the Chinese Academy of Sciences, particularly given that a lot of the mathematicians who had come back from abroad in recent years had ended up there. ‘While of course not every mathematician can do this kind of work,’ he said, ‘the person you need has to be a mathematician. You’ll have a lot more choice if you go there. I can give you some material which might help you locate the kind of person that you need.’

The material was all back at his work unit, so Director Tie told me to go with him to collect it. We all left the office together and just as we were standing by the entrance waiting for the car, he seemed to suddenly call someone to mind, and turned back to Director Tie to say, ‘If you could find her, I know someone who would be perfect for what you have in mind.’ He went on to explain that she had worked for the RAND Corporation in the United States, and that according to his information she had already broken a couple of Russian ciphers. Director Tie opened his eyes wide and asked how we could locate her. The captain explained that he had run across her at the Harbin Military Engineering University a couple of years earlier, and that she was very young and very pretty. Later on he heard that she had left, but he had no idea where she had gone.

‘What is she called?’

‘Huang Qian.’

‘With a name and address, I am sure we can find her.’ Director Tie then told us we would be splitting up. Bureau Chief Liu would be heading for the Harbin Military Engineering University to find Huang Qian, while I would be going to the Institute of Mathematics at the Chinese Academy of Sciences.

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